There are many barriers to wide scale adoption of photovoltaic systems in Arizona. Some of these are:

Costs

Suitable installation area

Electrical Code limits

Building Code requirements

Fire Code requirements

Homeowner Association rules

Electric Utility:

Policy/billing

Technical Limits

Legal

The cost of photovoltaic systems is continuing to decrease due to improvements in the technologies for photovoltaic modules and the inverters required to convert the dc electric power from the photovoltaic modules to regular ac electric power. Some items are increasing, such as wire, mounting structures, electrical apparatus (switches, meters, conduit). There are now many financing options to direct ownership that reduce or eliminate the upfront initial costs. The majority of residential photovoltaic systems being installed (2016) are now leased.

Many homes and commercial buildings simply do not have suitable areas for installing photovoltaic modules. Some residential developers actively design the roof orientations to make photovoltaic modules installation difficult or impossible, mostly because they find it easier to sell new homes in a development when they all look the same. This is not illegal, but is not in the spirit of an Arizona law (ARS: 33-439. Restrictions on installation or use of solar energy devices invalid; exception). There are utility restrictions on transporting electric power and water between properties, such as placing a photovoltaic on nearby property. More information on this is in <link to new article "Arizona Solar Laws">.

Safety is always a major concern. Except for some small low voltage photovoltaic systems (yard lights, etc.), many safety codes and standards apply in order to assure safe operation. The National Electrical Code, re-issued every three years, is the main electrical safety code, but there are requirements in Building and Fire codes that limit photovoltaic system installations. One relatively new requirement in the Building and Fire codes is to require clear access paths on roofs for first responders (firemen, etc.). Another relatively new requirement in the National Electrical Code (2017 version) requires that the roof mounted module area have an automatic shutdown such that when the ac power is disconnected all the voltages are reduced to safe levels (the dc voltages would otherwise increase when not connected). These requirements are generally reinforced in the building permit process.

In Arizona the electric utilities are essentially building barriers to photovoltaic systems by reducing direct and indirect incentives for photovoltaic systems. See the discussion in our Economics section Economics of Photovoltaics.

In some states, the electric utilities offer a billing option for Aggregated Net Billing wherein photovoltaic energy produced on one property or billing meter can be administratively applied to another account, perhaps with a small transaction fee.

Sometimes the existing utility electrical distribution system simply can not safely accept the proposed photovoltaic output. Those planning commercial size photovoltaic systems should check with the serving utility.